1. Field of the Invention
The present invention is directed to a mail processing machine of the type having a number of individual stations arranged in succession for conveying postal matter from station-to-station in order to process the postal matter, and in particular to an arrangement for communication among the stations of such a mail processing machine.
2. Description of the Prior Art
A mail processing machine of this type is suitable for processing filled letters of different formats given moderate through large shipping quantities. The structure composed of stations enables an economic adaptation to different customer demands. The system fashioned for communication can be operated as franking system, shipping system or postal matter evaluation system and can be quickly shut down in case of emergency.
Above a medium through higher number of letters or other postal matter to be sent, postage meter machines are utilized in a standard way for franking the postal matter. For example, U.S. Pat. No. 4,746,234 is directed to a thermal transfer postage meter machine that is surrounded by a secured housing.
U.S. Pat. No. 5,200,903 discloses connections of a personal computer or a work station via a multi-path cable to a peripheral postage meter machine that contains an accounting and control module (meter) and a printer, both for printing the franking stamp and for printing the receiver address. A modem is connected to the personal computer. The personal computer functions as a communication means and assumes the calculation of the respective postage fees for the individual items to be shipped on the basis of stored postage fee schedule tables. The peripheral accounting module is relieved of this calculating-intensive and memory-intensive function. An additional scale must be connected to the postage meter machine if the weight of the letter cannot be calculated by the personal computer on the basis of the letter content. The accounting module of the postage meter machine includes a processor system with postage memories and undertakes the accounting, and the directly connected control module controls the printing of address and franking stamp. The low working speed of the overall system is disadvantageous. The working speed is determined by the data transmission rate of the connection between the input/output part of the personal computer as well as by the accounting module. Moreover, it is up to the user to assure that the envelopes are printed with the correct value, or with the correct address. These solutions thus do not allow the automatic processing of filled letters having different thicknesses and different formats. A fast, automatic processing of mixed mail with postage fees that change from letter to letter is thus practically precluded.
Given a higher volume of mail, a mail processing system with postage meter machines, possibly together with other mail handling devices, is likewise utilized in a mail center for franking postal matter (see German Patent Applications 196 17 586.0, 196 17 473.2, 196 17 476.7, 196 17 557.7, respectively corresponding to pending U.S. application Ser. No.08/850,805, Ser. No.08/850,413, and Ser. No. 08/850,051, assigned to the same Assignee as the present application, whereby a scanner scans a bar code from the envelope in order to acquire an input information. This solution requires a computer-supported system in the office for prior application of the bar code onto the envelope. The postage meter machine controls the other devices accordingly. An intelligent scale for automatic postage calculation is also included.
Some mail processing machines are thus composed of stations having built-in intelligence. In general, such a mail processing machine is composed of a number of devices, for example of an automatic feeder station, a dynamic scale, a postage meter machine and a letter deposit. The devices are either centrally controlled or enter into communication with one another.
If, however, the number of connectable devices has an upper limit, an additional auxiliary device cannot be connected. Later customer needs for an auxiliary station, and thus for a flexible mail processing machine, then cannot be satisfied, merely for reasons of connection and control of the base station.
Given an increasing number of devices, each of which can be equipped with its own user interface, i.e. with its own display and with its own keyboard, the probability increases that error messages that are not overly serious are overlooked. Such error messages, however, can lead to further errors that can only be eliminated with a high expenditure of time.
When an error occurs, for example, because a device was opened, the respective device usually switches the supply voltage off. Corresponding, legal guidelines exist so that the user is protected against harm. When such an error occurs during a mail processing cycle, then a paper jam can arise when the postage meter machine is stopped but preceding devices continue to work for some time. The postal matter is crumpled or even destroyed given such jams. It is particularly time-consuming to eliminate such jams. Every malfunction has an especially disadvantageous effect, particularly given mail processing machines with a high mail processing volume.